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From:   Audra Mitchell <audra@redhat.com>
To:     linux-mm@kvack.org
Cc:     raquini@redhat.com, akpm@linux-foundation.org, djakov@kernel.org,
        vbabka@suse.cz, linux-kernel@vger.kernel.org
Subject: [PATCH 1/5] mm/page_owner: Remove free_ts from page_owner output
Date:   Fri, 13 Oct 2023 15:03:45 -0400
Message-ID: <20231013190350.579407-2-audra@redhat.com>
In-Reply-To: <20231013190350.579407-1-audra@redhat.com>
References: <20231013190350.579407-1-audra@redhat.com>
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When printing page_owner data via the sysfs interface, no free pages will
ever be dumped due to the series of checks in read_page_owner():

    /*
     * Although we do have the info about past allocation of free
     * pages, it's not relevant for current memory usage.
     */
     if (!test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags))

The free_ts values are still used when dump_page_owner() is called, so
keeping the field for other use cases but removing them for the typical
page_owner case.

Fixes: 866b48526217 ("mm/page_owner: record the timestamp of all pages during free")
Signed-off-by: Audra Mitchell <audra@redhat.com>
---
 mm/page_owner.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/page_owner.c b/mm/page_owner.c
index 4e2723e1b300..4f13ce7d2452 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -408,11 +408,11 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn,
 		return -ENOMEM;
 
 	ret = scnprintf(kbuf, count,
-			"Page allocated via order %u, mask %#x(%pGg), pid %d, tgid %d (%s), ts %llu ns, free_ts %llu ns\n",
+			"Page allocated via order %u, mask %#x(%pGg), pid %d, tgid %d (%s), ts %llu ns\n",
 			page_owner->order, page_owner->gfp_mask,
 			&page_owner->gfp_mask, page_owner->pid,
 			page_owner->tgid, page_owner->comm,
-			page_owner->ts_nsec, page_owner->free_ts_nsec);
+			page_owner->ts_nsec);
 
 	/* Print information relevant to grouping pages by mobility */
 	pageblock_mt = get_pageblock_migratetype(page);
-- 
2.41.0